Surrounding information collection system and surrounding information acquisition apparatus

ABSTRACT

A surrounding information collection system requests a vehicle to transmit surrounding information, and stores the surrounding information transmitted from the vehicle in response to the request. The surrounding information collection system requests a vehicle to transmit surrounding information, the vehicle acquiring the surrounding information having accuracy greater than a threshold calculated based on accuracy of the stored surrounding information.

BACKGROUND 1. Technical Field

The present disclosure relates to a surrounding information collectionsystem and a surrounding information acquisition apparatus.

2. Description of the Related Art

In order to implement automatic driving of a vehicle, it is required toestablish a dynamic map with high accuracy and high freshness. A dynamicmap is created from collecting various sets of surrounding informationacquired at respective places where vehicles travel and theirsurroundings (3D (three-dimensional) information, landmark information,traffic rule information, and so forth), and is updated as requiredbased on the latest surrounding information.

Surrounding information used to create and update a dynamic map can becollected, for example, by a vehicle management server that carries outcommunications with respective vehicles that actually travel at variousplaces, and receives information acquired by the vehicles that aretraveling, via a communications network.

Japanese Laid-Open Patent Application No. 2014-137743 discloses relatedart cases.

SUMMARY

According to one aspect of the present disclosure, a surroundinginformation collection system requests a vehicle to transmit surroundinginformation; and stores the surrounding information transmitted from thevehicle in response to the requesting. The surrounding informationcollection system requests a vehicle to transmit surroundinginformation, the vehicle acquiring the surrounding information havingaccuracy greater than a threshold calculated based on accuracy of thestored surrounding information.

Other objects, features and advantages will become more apparent fromthe following detailed description when read in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates one example of a system configuration of asurrounding information collection system;

FIG. 2 illustrates one example of a system configuration of asurrounding information acquisition apparatus;

FIG. 3A illustrates one example of a hardware configuration of a vehiclemanagement server and an information management server;

FIG. 3B illustrates one example of a hardware configuration of asurrounding information acquisition ECU;

FIG. 4A illustrates one example of area definition informationschematically for the sake of simplifying the explanation;

FIG. 4B illustrates one example of accuracy information definitiontables stored in an accuracy information definition table storage unit;

FIG. 5A illustrates one example of an accuracy information settingtable;

FIG. 5B illustrates one example of a surrounding information recordingresult;

FIG. 6 illustrates one example of dynamic map information;

FIG. 7 illustrates one example of a functional configuration of avehicle management server;

FIG. 8 illustrates relations between an “elapsed time from whensurrounding information was acquired” and a contribution degree;

FIG. 9 illustrates one example of a functional configuration of aninformation management server;

FIGS. 10 and 11 are sequence diagrams illustrating a surroundinginformation collection process in a surrounding information collectionsystem;

FIGS. 12-14 illustrate an actual example of the surrounding informationcollection process; and

FIG. 15 is a flowchart illustrating a flow of a surrounding informationanalysis process in the surrounding information collection system.

DETAILED DESCRIPTION OF EMBODIMENTS

If a vehicle management server receives all surrounding informationacquired by vehicles that are traveling, the communications trafficrequired between the vehicles and the vehicle management server may bevery high, in particular, in a traffic area such as a main road. As aresult, the high communications cost may be required, and thecommunications network in the area may become congested.

Surrounding information acquired by vehicles that are traveling mayinclude surrounding information with accuracy lower than accuracy ofsurrounding information that the vehicle management server has alreadycollected. Such surrounding information may have a low contribution tocreating and updating a dynamic map, and therefore, even if suchsurrounding information is not collected, creation and update of thedynamic map may be hardly affected.

Embodiments of the present invention have an object to limit targets tocollect when collecting surrounding information acquired by vehicles viaa communications network based on accuracy of surrounding information,to reduce communications traffic required to collect surroundinginformation.

Below, the embodiments of the present invention will be described withreference to the accompanying drawings. In the description of theembodiment below, a “sensor type” denotes a type of a surroundinginformation acquisition sensor installed in a vehicle to detectsurrounding information at each place where the vehicle travels and theperiphery of the place (for example, a 3D scanner apparatus, an imagingapparatus, a millimeter-wave radar apparatus, or the like). A “producttype” denotes a type of a product that belongs to each sensor type of asurrounding information acquisition sensor (for example, a productname). “Type information” denotes information that indicates a type ofsurrounding information (for example, target information, imageinformation, distance information, or the like).

“Accuracy information” denotes information that indicates accuracy ofsurrounding information, and is a value acquired by evaluating, on ascale of one through seven, accuracy of surrounding information detectedby a product that belongs to each sensor type.

An “accuracy information definition table” denotes a table whereproducts that belong to each sensor type are classified into sevengroups according to the accuracy, and accuracy information 1 through 7is associated with the respective groups. “Accuracy information=7”(i.e., accuracy information that indicates the highest accuracy) meansthat surrounding information detected by a product has the highestaccuracy, and “accuracy information=1” (i.e., accuracy information thatindicates the lowest accuracy) means that surrounding informationdetected by a product has the lowest accuracy.

An “accuracy information setting table” denotes a table where accuracyinformation of each of surrounding information acquisition sensorsinstalled in each vehicle is set for a vehicle based on the accuracyinformation definition table. In the accuracy information setting table,information that indicates a product type, accuracy information, andtype information of a surrounding information acquisition sensorinstalled in each vehicle are associated with each other.

A “contribution degree” denotes a degree of contribution at the presenttime for using peripheral information acquired through a surroundinginformation acquisition sensor to create or update a dynamic map. It ispossible to calculate a contribution degree of surrounding informationat the present time by correcting the accuracy information of thesurrounding information detected by a surrounding informationacquisition sensor based on the elapsed time (freshness) from when thesurrounding information was acquired. Note that, in the embodiments thatwill now be described, surrounding information contributes to creatingor updating a dynamic map. However, a target (i.e., a use) to whichsurrounding information contributes need not be limited, and it ispossible to use a term “serviceability” that indicates a utility valueof surrounding information, instead of the term “contribution degree”.The term “serviceability” has a broader meaning than the term“contribution degree”.

Below, the embodiments will be described in detail. Note that, throughthe specification and drawings, the same reference numerals are given toelements that have substantially the same functional configurations, andduplicate description will be omitted.

Embodiments <1. Configuration of Surrounding Information CollectionSystem>

First, a system configuration of a surrounding information collectionsystem according to an embodiment will be described. FIG. 1 illustratesone example of a system configuration of a surrounding informationcollection system. As illustrated in FIG. 1, the surrounding informationcollection system 100 includes a vehicle management server 110, aninformation management server 120, and a surrounding informationacquisition system 140 installed in a vehicle 130.

In the surrounding information collection system 100, the vehiclemanagement server 110 and the information management server 120 arecommunicatably connected via a network 150. In the same way, the vehiclemanagement server 110 and the surrounding information acquisition system140 are communicatably connected via the network 150.

The vehicle management server 110 is a server apparatus that manages thevehicle 130. In the present embodiment, a contribution degreedetermination program is installed in the vehicle management server 110.The vehicle management server 110 functions as a contributiondetermination unit 111 as a result of executing the contribution degreedetermination program.

If the contribution determination unit 111 has received attributioninformation (i.e., information that indicates an attribute ofsurrounding information that the vehicle 130 has acquired) from thevehicle 130, the contribution determination unit 111 determines, basedon the received attribution information, whether to request the vehicle130 to transmit the surrounding information. If the contributiondetermination unit 111 has determined to request the vehicle 130 totransmit the surrounding information, the contribution determinationunit 111 requests the vehicle 130 to transmit the surroundinginformation, and receives the surrounding information from the vehicle130. Also, the contribution determination unit 111 generates updateinformation that includes the received surrounding information, andupdates a dynamic map information storage unit 122. On the other hand,if the contribution determination unit 111 has determined to not requestthe vehicle 130 to transmit the surrounding information, thecontribution determination unit 111 does not request the vehicle 130 totransmit the surrounding information.

When the contribution determination unit 111 determines whether torequest the vehicle 130 to transmit the surrounding information, thecontribution determination unit 111 reads an area definition informationstorage unit 112 based on position information (information thatindicates the position where the vehicle 130 was when the vehicleacquired the surrounding information) included in the attributioninformation. Thus, the contribution determination unit 111 determineswhich one of previously defined areas (for example, respective blockseach having a size of 10 m by 10 m acquired from dividing each placewhere the vehicle 130 travels) corresponds to the position informationincluded in the attribution information.

Then, the contribution determination unit 111 acquires informationconcerning a surrounding information collection situation from theinformation management server 120 based on area information thatindicates the determined area and type information included in theattribution information.

Actually, the contribution determination unit 111 acquires the number ofsets of surrounding information already stored in the dynamic mapinformation storage unit 122 from the information management server 120.Note that the number of sets of surrounding information (hereinafter,also referred to as the number of stored sets) that the contributiondetermination unit 111 thus acquires is the number of sets ofsurrounding information to each of which the determined area informationand the type information included in the attribution information areassociated.

Also, the contribution determination unit 111 acquires the lowestcontribution degree from among the contribution degrees of therespective sets of surrounding information already stored in the dynamicmap information storage unit 122, from the information management server120. Note that the lowest contribution degree that the contributiondetermination unit 111 thus acquires is the lowest contribution degree(hereinafter, referred to as the “contribution degree lowest value”)from among the contribution degrees of the sets of surroundinginformation with each of which the determined area information and thetype information included in the attribution information are associated.

Then, the contribution determination unit 111 determines whether torequest the vehicle 130 to transmit the surrounding information, basedon the information concerning the surrounding information collectionsituation (i.e., the number of stored sets and the contribution degreelowest value).

Note that when the contribution determination unit 111 determineswhether to request the vehicle 130 to transmit the surroundinginformation based on the information concerning the surroundinginformation collection situation, the contribution determination unit111 uses the accuracy information (i.e., the accuracy information of thesurrounding information that the vehicle 130 acquires) included in thereceived attribution information. The accuracy information is determinedbased on an accuracy information setting table (not illustrated inFIG. 1) that is set in a surrounding information acquisition apparatus142.

The information management server 120 is a server apparatus that managesthe dynamic map information storage unit 122 that is one example of astorage unit that stores surrounding information. In the presentembodiment, an information management program is installed in theinformation management server 120, and the information management server120 functions as an information management unit 121 by executing theinformation management program.

If the information management unit 121 has received update informationfrom the vehicle management server 110, the information management unit121 updates the dynamic map information storage unit 122. Also, theinformation management unit 121 reads the dynamic map informationstorage unit 122 based on the area information and the type informationtransmitted from the vehicle management server 110, and determines theinformation concerning the surrounding information collection situation.Also, the information management unit 121 transmits the determinedinformation concerning the surrounding information collection situationto the vehicle management server 110.

Actually, the information management unit 121 calculates the number ofsets of surrounding information (the number of stored sets) associatedwith the area information and the type information transmitted from thevehicle management server 110 from among the sets of surroundinginformation already stored in the dynamic map information storage unit122. Also, the information management unit 121 transmits the calculatednumber of stored sets to the vehicle management server 110.

Also, the information management unit 121 calculates the respectivecontribution degrees of the sets of surrounding information associatedwith the area information and the type information transmitted from thevehicle management server 110 from among the sets of surroundinginformation already stored in the dynamic map information storage unit122. Also, the information management unit 121 transmits the lowestcontribution degree (the contribution degree lowest value) from amongthe calculated contribution degrees to the vehicle management server110.

The surrounding information acquisition system 140 has a DCM 141 and thesurrounding information acquisition apparatus 142. The DCM 141 is acommunications apparatus that connects to the vehicle management server110 via the network 150.

The surrounding information acquisition apparatus 142 acquiressurrounding information through a surrounding information acquisitionsensor. Also, if the surrounding information acquisition apparatus 142has acquired surrounding information, the surrounding informationacquisition apparatus 142 transmits the attribution information to thevehicle management server 110. Also, if the surrounding informationacquisition apparatus 142 has received a request from the vehiclemanagement server 110 to transmit surrounding information, thesurrounding information acquisition apparatus 142 transmits therequested surrounding information to the vehicle management server 110.Note that, a configuration of the surrounding information acquisitionapparatus 142 will be described in detail with reference to FIG. 2.

<2. System Configuration of Surrounding Information AcquisitionApparatus>

FIG. 2 illustrates one example of a system configuration of thesurrounding information acquisition apparatus. As illustrated in FIG. 2,the surrounding information acquisition apparatus 142 includes aposition information acquisition unit 211, a time informationacquisition unit 212, and a surrounding information acquisition ECU 200.Also, the surrounding information acquisition apparatus 142 includes afirst surrounding information acquisition sensor 221, a secondsurrounding information acquisition sensor 222, a third surroundinginformation acquisition sensor 223, and so forth.

The position information acquisition unit 211 calculates positioninformation (the latitude, the longitude, and the altitude) thatindicates the current position of the vehicle 130 based on, for example,information acquired from GPS (Global Positioning System). The positioninformation acquisition unit 211 outputs the calculated positioninformation to the surrounding information acquisition ECU 200.

The time information acquisition unit 212 acquires time informationthrough, for example, a clock function built in the time informationacquisition unit 212, and outputs the time information to thesurrounding information acquisition ECU 200.

The first, second, and third surrounding information acquisition sensors221, 222, and 223 are sensors that detect surrounding information atrespective places where the vehicle 130 travels, and their surroundingplaces. The first surrounding information acquisition sensor 221 is, forexample, a 3D scanner apparatus (i.e., a product name: “S05/2015”), andoutputs detected target information to the surrounding informationacquisition ECU 200 as surrounding information. The second surroundinginformation acquisition sensor 222 is, for example, an imaging apparatus(i.e., product name: “IM01/2014”), and outputs detected imageinformation to the surrounding information acquisition ECU 200 assurrounding information. The third surrounding information acquisitionsensor 223 is, for example, a millimeter-wave radar apparatus (i.e.,product name: “L01/2013”), and outputs detected distance information tothe surrounding information acquisition ECU 200 as surroundinginformation.

Note that surrounding information includes information that indicatesthe product type of the surrounding information acquisition sensor thatoutputs the surrounding information (for example, the product name).

In the surrounding information acquisition ECU 200, a surroundinginformation acquisition program, an attribution information transmissionprogram, and a surrounding information transmission program areinstalled. The surrounding information acquisition ECU 200 executes thesurrounding information acquisition program, the attribution informationtransmission program, and the surrounding information transmissionprogram, to function as a surrounding information acquisition unit 201,an attribution information transmission unit 202, and a surroundinginformation transmission unit 203.

The surrounding information acquisition unit 201 is one example of anacquisition unit, and acquires surrounding information that is outputfrom the first, second and third surrounding information acquisitionsensors 221, 222, 223, and so forth. Also, the surrounding informationacquisition unit 201 associates the acquired surrounding informationwith the position information acquired from the position informationacquisition unit 211 and the time information acquired from the timeinformation acquisition unit 212, and records the surroundinginformation, the position information, and the time information in asurrounding information recording unit 205.

Also, the surrounding information acquisition unit 201 reads an accuracyinformation setting table storage unit 204 to determine the accuracyinformation of the acquired surrounding information. Also, thesurrounding information acquisition unit 201 associates the determinedaccuracy information with the acquired surrounding information, andrecords the accuracy information in the surrounding informationrecording unit 205.

Also, the surrounding information acquisition unit 201 reads theaccuracy information setting table storage unit 204 to determine thetype information of the acquired surrounding information. Also, thesurrounding information acquisition unit 201 associates the determinedtype information with the acquired surrounding information, and recordsthe type information in the surrounding information recording unit 205.

If the surrounding information is recorded in the surroundinginformation recording unit 205, the attribution information transmissionunit 202 reads the also recorded position information, time information,accuracy information, and type information associated with thesurrounding information, to generate the attribution information.

Also, the attribution information transmission unit 202 transmits thegenerated attribution information to the vehicle management server 110via the DCM 141.

Also, the attribution information transmission unit 202 determineswhether the attribution information transmission unit 202 has received arequest to transmit the surrounding information within a predeterminedperiod of time from when the attribution information transmission unit202 transmitted the attribution information to the vehicle managementserver 110. If the attribution information transmission unit 202 hasdetermined that the attribution information transmission unit 202 hasreceived a request to transmit the surrounding information within thepredetermined period of time, the attribution information transmissionunit 202 transmits the determination result to the surroundinginformation transmission unit 203. On the other hand, if the attributioninformation transmission unit 202 has determined that the attributioninformation transmission unit 202 has not received a request to transmitthe surrounding information within the predetermined period of time, theattribution information transmission unit 202 discards the surroundinginformation (for which a request to transmit has not been received)recorded in the surrounding information recording unit 205, andtransmits a request invalid response to the vehicle management server110.

If the surrounding information transmission unit 203 has received thedetermination result from the attribution information transmission unit202, the surrounding information transmission unit 203 reads thecorresponding surrounding information recorded in the surroundinginformation recording unit 205. Also, the surrounding informationtransmission unit 203 transmits a vehicle ID to identify the vehicle 130and the read surrounding information to the vehicle management server110 via the DCM 141. If the surrounding information transmission unit203 has not received the determination result from the attributioninformation transmission unit 202, the surrounding informationtransmission unit 203 does not transmit the surrounding information tothe vehicle management server 110.

<3. Hardware Configuration of Vehicle Management Server and InformationManagement Server, and Hardware Configuration of Surrounding InformationAcquisition ECU>

Next, hardware configurations of the vehicle management server 110 andthe information management server 120 and a hardware configuration ofthe surrounding information acquisition ECU 200 will be described. Notethat because hardware configurations of the vehicle management server110 and the information management server 120 are approximately the sameas one another, the hardware configuration of the vehicle managementserver 110 will now be described. FIG. 3A illustrates one example of ahardware configuration of the vehicle management server.

As illustrated in FIG. 3A, the vehicle management server 110 includes aCPU (Central Processing Unit) 301, a ROM (Read-Only Memory) 302, a RAM(Random Access Memory) 303, an auxiliary storage unit 304, a userinterface unit 305, and a communications unit 306. The respective unitsin the vehicle management server 110 are mutually connected via a bus307.

The CPU 301 is a processor that executes a program stored in the ROM 304and a program (such as the contribution degree determination program)stored in the auxiliary storage unit 304. For executing a program, theCPU 301 uses information (area definition information, the accuracyinformation definition table, or the like) stored in the auxiliarystorage unit 304.

The user interface unit 305 is used for inputting other information usedby the CPU 301 for executing a program, and displays informationgenerated when the CPU 301 has executed the program.

The communications unit 306 connects to the network 150, and carries outcommunications with respective apparatuses (the information managementserver 120 and the surrounding information acquisition system 140) viathe network 150.

FIG. 3B illustrates one example of a hardware configuration of thesurrounding information acquisition ECU 200. As illustrated in FIG. 3B,the surrounding information acquisition ECU 200 includes a CPU 331, aRAM 332, a connection unit 333, and an EEPROM (Electrically ErasableProgrammable Read-Only Memory) 334. The CPU 331 executes the surroundinginformation acquisition program, the attribution informationtransmission program, and the surrounding information transmissionprogram stored in the EEPROM 334 using the RAM 332 or the like as a workarea. The CPU 331 reads the accuracy information setting table storageunit 204 in the EEPROM 334 when executing these programs. Also,surrounding information and so forth acquired as a result of the CPU 331executing these programs are recorded in the surrounding informationrecording unit 205 stored in the EEPROM 334.

The connection unit 333 connects the respective units (the positioninformation acquisition unit 211, the time information acquisition unit212, the first surrounding information acquisition sensors 221-223, theDCM 141, and so forth).

<4. Area Definition Information and Accuracy Information DefinitionTable in Vehicle Management Server>

Next, the area definition information stored in the area definitioninformation storage unit 112, and the accuracy information definitiontable stored in the accuracy information definition table storage unit113 in the vehicle management server 110, will be described. FIG. 4Aillustrates one example of the area definition information schematicallyfor the sake of simplifying the explanation.

As illustrated in FIG. 4A, the area definition information 400 is suchthat each area where the vehicle 130 travels is divided into, forexample, square blocks each having a size of 10 m by 10 m, an area nameis given to each block, and a relation between the position and the areais prescribed. Concerning the example of FIG. 4A, as illustrated, “areaname=area A” is given to a block 401 representing a certain position inan actual space; “area name=area B” is given to a block 402 representinganother position in the actual space; and “area name=area C” is given toa block 403 representing yet another position in the actual space.

By reading the area definition information 400 described above, thecontribution determination unit 111 can determine the area correspondingto the position information concerning the vehicle 130 that istraveling.

FIG. 4B illustrates one example of the accuracy information definitiontables stored in the accuracy information definition table storage unit113. As illustrated in FIG. 4B, the accuracy information definitiontable storage unit 113 stores the accuracy information definition tablesseparately for the respective sensor types. The accuracy informationdefinition table 410 is an accuracy information definition table for“sensor type=3D scanner apparatus” where the product types of productsclassified as 3D scanner apparatuses are further classified into sevengroups according to the accuracy.

The accuracy information definition table 410 includes, as informationitems, “accuracy information” and “information indicating product type”.As the item “accuracy information”, accuracy information of any one ofthe seven grades 1-7 is stored. As the item “information indicatingproduct type”, a product name (or a product type) of each product isstored as information that indicates a product type classified as a 3Dscanner apparatus and is associated with the corresponding accuracyinformation.

In the same way, the accuracy information definition table 420 is anaccuracy information definition table for “sensor type=imagingapparatus” where the product types of products classified as imagingapparatuses are further classified into seven groups according to theaccuracy. The accuracy information definition table 430 is an accuracyinformation definition table for “sensor type=millimeter-wave radarapparatus” where the product types of products classified asmillimeter-wave radar apparatuses are further classified into sevengroups according to the accuracy.

<5. Accuracy Information Setting Table and Surrounding InformationRecording Result in Surrounding Information Acquisition ECU>

Next, the accuracy information setting table stored in the accuracyinformation setting table storage unit 204, and the surroundinginformation recording result stored in the surrounding informationrecording unit 205, in the surrounding information acquisition ECU 200,will be described. FIGS. 5A and 5B illustrate examples of the accuracyinformation setting table and the surrounding information recordingresult, respectively.

The accuracy information setting table 500 is generated based on theaccuracy information definition tables 410-430, and so forth, of FIG.4B, and is set for each vehicle. The example of FIG. 5A is the accuracyinformation setting table that is set for the vehicle 130 of “vehicleID=C1”.

As illustrated in FIG. 5A, the accuracy information setting table 500prescribes the sensor types, the accuracy information, and the typeinformation for all the surrounding information acquisition sensorsinstalled in the vehicle 130. Therefore, the accuracy informationsetting table 500 has, as information items, “information indicatingproduct type”, “sensor type”, “accuracy information”, and “typeinformation”.

In the item “information indicating product type”, the informationindicating the product types (product names) of all the surroundinginformation acquisition sensors installed in the vehicle 130 of “vehicleID=C1” is included. According to the example of FIG. 5A, the vehicle 130of “vehicle ID=C1” has the surrounding information acquisition sensorsof “product name=S05/2015”, “product name=IM01/2014”, and “productname=L01/2013”.

In the item “sensor type”, the sensor types of the respectivesurrounding information acquisition sensors are stored. In the item“accuracy information”, the accuracy information concerning thesurrounding information detected by each surrounding informationacquisition sensor is stored. In the item “type information”, the typeinformation concerning the surrounding information detected by eachsurrounding information acquisition sensor is stored.

According to the example of FIG. 5A, the first surrounding informationacquisition sensor 221 of “product name=S05/2015” is a 3D scannerapparatus that detects target information having the highest accuracy(“accuracy information=7”) from among 3D scanner apparatuses that detecttarget information. Also, the second surrounding information acquisitionsensor 222 of “product name=IM01/2014” is an imaging apparatus thatdetects image information having the fourth accuracy (“accuracyinformation=4”) from among imaging apparatuses that detect imageinformation. Also, the third surrounding information acquisition sensor223 of “product name=L01/2013” is a millimeter-wave radar apparatus thatdetects distance information having the lowest accuracy (“accuracyinformation=1”) from among millimeter-wave radar apparatuses that detectdistance information.

Note that the accuracy information stored in the item “the accuracyinformation” of the accuracy information setting table 500 may bechanged with time. For example, the first surrounding informationacquisition sensor 221 of “product name=S05/2015” is a 3D scannerapparatus that detects target information of the highest accuracy at thepresent time from among the 3D scanner apparatuses included in thevehicle, according to the accuracy information definition table 410.However, for example, if a new 3D scanner apparatus that detects targetinformation of higher accuracy (“accuracy information=7”) has beenincluded in the vehicle, the accuracy information definition table 410of FIG. 4B will be changed. As a result, the accuracy of targetinformation detected by the first surrounding information acquisitionsensor 221 is relatively reduced accordingly. Thus, with time, theaccuracy information definition table 410 of FIG. 4B may be changed, andtherefore, it is desirable that also the accuracy information stored inthe item “the accuracy information” of the accuracy information settingtable 500 of FIG. 5 may be changed with time.

Next, the surrounding information recording result 510 will bedescribed. As illustrated in FIG. 5B, the surrounding informationrecording result 510 is recorded, is associated with the vehicle ID,and, as information items, “time information”, “position information”,“accuracy information”, “type information”, and “surroundinginformation” are included.

In the item “time information”, time information that indicates the timewhen the corresponding surrounding information was recorded in thesurrounding information recording unit 205 is recorded. In the item“position information”, position information that indicates the positionwhere the surrounding information was recorded in the surroundinginformation recording unit 205 is recorded.

In the item “accuracy information”, the accuracy information of thecorresponding surrounding information is recorded. The accuracyinformation is determined by reading the accuracy information settingtable 500. In the item “type information”, the type information of thecorresponding surrounding information is recorded. The type informationis determined by reading the accuracy information setting table 500. Inthe item “surrounding information”, the corresponding acquiredsurrounding information is recorded.

According to the example of FIG. 5B, the vehicle 130 identified by“vehicle ID=C1” recorded the surrounding information at a time of “timeinformation=2015/11/5 10:23” (i.e., 10:23 on Nov. 5, 2015) at a place ofposition information=(X11, Y11, Z11). Also, according to the example ofFIG. 5B, the recorded surrounding information has the accuracy of“accuracy information=7”, has data name “3D target information 1-001”,and belongs to “type information=target information”. Note that, in FIG.5B, the data name (for example, “3D target information 1-001”) of eachset of surrounding information is mentioned in the item “surroundinginformation” for the sake of simplifying the explanation. Actually, inthe item “surrounding information”, the corresponding set of surroundinginformation itself is stored.

<6. Dynamic Map Information of Information Management Server>

Next, the dynamic map information stored in the dynamic map informationstorage unit 122 of the information management server 120 will bedescribed. FIG. 6 illustrates one example of the dynamic mapinformation.

As illustrated in FIG. 6, in the dynamic map information storage unit122, the dynamic map information is managed for each area name, and isclassified for each type information. In FIG. 6, the dynamic mapinformation 601 is dynamic map information for “area name=area A” and“type information=target information”. In the same way, the dynamic mapinformation 602 is dynamic map information for “area name=area A” and“type information=image information”. The dynamic map information 603 isdynamic map information for “area name=area A” and “typeinformation=distance information”.

In the same way, the dynamic map information 611 is dynamic mapinformation for “area name=area B” and “type information=targetinformation”. The dynamic map information 612 is dynamic map informationfor “area name=area B and “type information=image information”. Thedynamic map information 613 is dynamic map information for “areaname=area B” and “type information=distance information”.

Thus, the dynamic map information storage unit 122 has the number ofsets of dynamic map information corresponding to the number ofrespective items of type information for each area.

Each of the respective sets of dynamic map information (601 through 603,and 611 through 613) has, as information items, “time information”,“position information”, “accuracy information”, “surroundinginformation”, and “vehicle ID”.

In the item “time information”, the time information included in theupdate information transmitted from the vehicle management server 110 isstored. Note that the time information included in the updateinformation indicates the time when surrounding information detected bya surrounding information acquisition sensor was recorded in thesurrounding information recording unit 205.

In the item “position information”, the position information included inthe update information transmitted from the vehicle management server110 is stored. Note that the position information included in the updateinformation indicates the position of the corresponding vehicle wherethe surrounding information detected by the surrounding informationacquisition sensor was recorded in the surrounding information recordingunit 205.

In the item “accuracy information”, the accuracy information included inthe update information transmitted from the vehicle management server110 is stored. Note that the accuracy information included in the updateinformation indicates the accuracy of the surrounding informationdetected by the surrounding information acquisition sensor.

In the item “surrounding information”, the surrounding informationincluded in the update information transmitted from the vehiclemanagement server 110 is stored. In the item “vehicle ID”, theidentifier (ID) of the vehicle included in the update informationtransmitted from the vehicle management server 110 is stored.

Thus, in each of the respective sets of dynamic map information (601through 603, and 611 through 613) stored in the dynamic map informationstorage unit 122, the time information, the position information, theaccuracy information, and the vehicle ID are associated with thesurrounding information, and are stored.

According to the first record in the example of the dynamic mapinformation 601, surrounding information (data name “3Dtargetinformation 1-001”) was recorded at the time of “timeinformation=2015/11/5 10:23” (i.e., 10:23 on Nov. 5, 2015) at the placeof position information=(X11, Y11, Z11) included in the area A. Also,according to the first record in the example of the dynamic mapinformation 601, the surrounding information has the accuracy of“accuracy information=7”, and was transmitted from the vehicle 130identified by “vehicle ID=C1”.

According to the first record in the example of the dynamic mapinformation 611, the vehicle 130 identified by “vehicle ID=C1” moved tothe place of “position information=(X21, Y21, Z21)” included in the areaB, 1 minute later (i.e., “time information=2015/11/5 10:24”) (i.e.,10:24 on Nov. 5, 2015). Also, according to the first record in theexample of the dynamic map information 611, the same vehicle 130acquired surrounding information (data name “3D target information1-002”) having the accuracy of “accuracy information=7”.

Note that, also in FIG. 6, the data name (for example, “3D targetinformation 1-001”) of each set of surrounding information is mentionedin the item “surrounding information” for the sake of simplifying theexplanation. Actually, in the item “surrounding information”, thecorresponding set of surrounding information itself is stored.

<7. Functional Configuration of Vehicle Management Server>

Next, a functional configuration of the vehicle management server 110will be described in detail. FIG. 7 illustrates one example of afunctional configuration of the vehicle management server. Asillustrated in FIG. 7, the vehicle management server 110 that functionsas the contribution determination unit 111 includes an attributeinformation reception unit 701, a number-of-stored-sets determinationunit 702, a contribution calculation unit 703, a comparison unit 704, atransmission requesting unit 705, and a surrounding informationreception unit 706. The vehicle management server 110 that functions asthe contribution determination unit 111 further includes an updateinstruction unit 707 and a surrounding information analysis unit 708.

The attribute information reception unit 701 is one example of areception unit, and receives the attribution information transmittedfrom the surrounding information acquisition apparatus 142 of thevehicle 130, via the network 150. Also, the attribute informationreception unit 701 extracts the time information, the positioninformation, the type information, and the accuracy information from thereceived attribution information. Also, the attribute informationreception unit 701 reads the area definition information 400 from thearea definition information storage unit 112, and determines the areacorresponding to the extracted position information. Also, the attributeinformation reception unit 701 sends the area information that indicatesthe determined area, and the extracted type information to thenumber-of-stored-sets determination unit 702. Also, the attributeinformation reception unit 701 sends the area information that indicatesthe determined area and the extracted type information and accuracyinformation to the contribution calculation unit 703.

The number-of-stored-sets determination unit 702 requests theinformation management server 120 to calculate the number of stored setsof surrounding information. Actually, the number-of-stored-setsdetermination unit 702 requests the information management server 120 tocalculate the number of stored sets of surrounding informationassociated with the area information and type information that have beensent from the attribute information reception unit 701.

When the information management server 120 has transmitted informationthat indicates the number of stored sets in response to the request ofthe number-of-stored-sets determination unit 702 to calculate the numberof stored sets, the number-of-stored-sets determination unit 702determines whether the number of stored sets indicated by thetransmitted information is greater than or equal to a predeterminednumber.

If the number-of-stored-sets determination unit 702 has determined thatthe number of stored sets indicated by the transmitted information isless than the predetermined number, the number-of-stored-setsdetermination unit 702 sends the determination result to thetransmission requesting unit 705. If the number-of-stored-setsdetermination unit 702 has determined that the number of stored setsindicated by the transmitted information is greater than or equal to thepredetermined number, the number-of-stored-sets determination unit 702sends the determination result to the contribution calculation unit 703.

When the contribution calculation unit 703 has received thedetermination result that the number of stored sets is greater than orequal to the predetermined number from the number-of-stored-setsdetermination unit 702, the contribution calculation unit 703 requeststhe information management server 120 to calculate the contributiondegree lowest value, using the area information and type informationthat have been sent from the attribute information reception unit 701.

In response to the request to calculate the contribution degree lowestvalue, the information management server 120 transmits information thatindicates the contribution degree lowest value that is the lowestcontribution degree from among the contribution degrees calculated forthe respective sets of surrounding information associated with the areainformation and the type information included in the request made by thecontribution calculation unit 703. The contribution calculation unit 703acquires the transmitted information.

Also, the contribution calculation unit 703 calculates the contributiondegree for the accuracy information that has been sent from theattribute information reception unit 701, and sends the calculatedcontribution degree to the comparison unit 704 together with thecontribution degree lowest value that has been transmitted from theinformation management server 120.

Note that, in the present embodiment, the contribution degree iscalculated by the following formula.

contribution degree=accuracy information×Exp(x)

where x=−(elapsed time from when surrounding information wasacquired)/Tc

where Tc denotes a time constant

Actually, when the contribution calculation unit 703 calculates thecontribution degree, the contribution calculation unit 703 substitutes“0” for the “elapsed time from when surrounding information wasacquired” (as a result, the contribution calculation unit 703 calculatesthe contribution degree to be the accuracy information itself).

When the information management server 120 calculates the contributiondegree of each set of surrounding information in response to a requestto calculate the contribution degree lowest value, the informationmanagement server 120 calculates the “elapsed time from when surroundinginformation was acquired” based on the present time and the timeinformation associated with the set of surrounding information. Notethat the “present time” means, for example, the time when the attributeinformation reception unit 701 has received the attribution information.Then, the information management server 120 calculates the contributiondegree by substituting the “accuracy information” associated with theset of surrounding information, and the calculated “elapsed time fromwhen surrounding information was acquired” in the above formula. Thus,the information management server 120 calculates the changedcontribution degree acquired from reducing the accuracy information ofthe set of surrounding information according to the “elapsed time fromwhen surrounding information was acquired”.

FIG. 8 illustrates relations between the “elapsed time from whensurrounding information was acquired” and the corresponding contributiondegree. As illustrated in FIG. 8, when the elapsed time is “0”, thecontribution degree is equal to the accuracy information, and thecontribution degree gradually reduces with time.

Returning to the description of FIG. 7, the comparison unit 704 is oneexample of a determination unit, and determines whether the contributiondegree sent from the contribution calculation unit 703 is greater thanthe contribution degree lowest value. If the comparison unit 704 hasdetermined that the contribution degree sent from the contributioncalculation unit 703 is greater than the contribution degree lowestvalue, the comparison unit 704 sends the determination result to thetransmission requesting unit 705. Thus, the comparison unit 704 uses thecontribution degree lowest value as a threshold for determining whetherto send the determination result to the transmission requesting unit705.

When the transmission requesting unit 705 has received the determinationresult from the number-of-stored-sets determination unit 702, thetransmission requesting unit 705 functions as a second transmissionrequesting unit that requests the surrounding information acquisitionsystem 140 of the vehicle 130 to transmit the surrounding information.Also, when the transmission requesting unit 705 has received thedetermination result from the comparison unit 704, the transmissionrequesting unit 705 functions as a first transmission requesting unitthat requests the surrounding information acquisition system 140 of thevehicle 130 to transmit the surrounding information. Note that, if thetransmission requesting unit 705 has not received the determinationresult from either of the number-of-stored-sets determination unit 702and the comparison unit 704, the transmission requesting unit 705 doesnot request the surrounding information acquisition system 140 of thevehicle 130 to request to transmit the surrounding information.

If the surrounding information acquisition system 140 of the vehicle 130has transmitted the surrounding information and the vehicle ID inresponse to a request of the transmission requesting unit 705 totransmit surrounding information, the surrounding information receptionunit 706 receives the surrounding information and the vehicle ID. Also,the surrounding information reception unit 706 associates the receivedsurrounding information and vehicle ID with the attribution informationreceived by the attribute information reception unit 701 and the areainformation that indicates the area determined by the attributeinformation reception unit 701, and sends the surrounding information,the vehicle ID, the attribution information, and the area information tothe update instruction unit 707.

The update instruction unit 707 transmits the received surroundinginformation, vehicle ID, attribution information, and area informationas the update information together with an update instruction to theinformation management server 120.

The surrounding information analysis unit 708 monitors the transmissionrequesting unit 705 and the update instruction unit 707. Then, if thedynamic map information storage unit 122 of the information managementserver 120 has been updated, the surrounding information analysis unit708 increases the score of the user of the vehicle which has contributedto the update. Actually, if the transmission requesting unit 705 hasrequested to transmit the surrounding information, the surroundinginformation analysis unit 708 determines whether the request has beenmade in response to the information that is sent from thenumber-of-stored-sets determination unit 702 or the information that issent from the comparison unit 704. If the surrounding informationanalysis unit 708 has determined that the request has been made inresponse to the information from the comparison unit 704, thesurrounding information analysis unit 708 increases the score of theuser of the vehicle that has transmitted the surrounding information inresponse to the request to transmit the surrounding information.

<8. Functional Configuration of Information Management Server>

Next, a functional configuration of the information management server120 will be described. FIG. 9 illustrates one example of a functionalconfiguration of the information management server 120. As illustratedin FIG. 9, the information management server 120 that functions as thenumber-of-stored-sets calculation unit 901 includes anumber-of-stored-sets calculation unit 901, a contribution degree lowestvalue calculation unit 902 and an update unit 903.

When the number-of-stored-sets calculation unit 901 has received therequest to calculate the number of stored sets from the vehiclemanagement server 110, the number-of-stored-sets calculation unit 901extracts the area information and the type information from the requestto calculate the number of stored sets. Also, the number-of-stored-setscalculation unit 901 reads the dynamic map information storage unit 122based on the extracted area information and type information. Then, thenumber-of-stored-sets calculation unit 901 calculates the number ofstored sets of surrounding information (the number of stored sets)concerning the dynamic map information (for example, the dynamic mapinformation 601) associated with the extracted area information and typeinformation. The number-of-stored-sets calculation unit 901 transmitsinformation that indicates the calculated number of stored sets to thevehicle management server 110.

When the contribution degree lowest value calculation unit 902 hasreceived the request to calculate the contribution degree lowest valuefrom the vehicle management server 110, the contribution degree lowestvalue calculation unit 902 extracts the area information and the typeinformation from the request to calculate the contribution degree lowestvalue. Also, the contribution degree lowest value calculation unit 902reads the dynamic map information storage unit 122 based on theextracted area information and type information. Then, the contributiondegree lowest value calculation unit 902 acquires the time informationand the accuracy information of each of the stored sets of surroundinginformation concerning the dynamic map information (for example, thedynamic map information 601) associated with the extracted areainformation and type information.

Also, the contribution degree lowest value calculation unit 902calculates the contribution degree of each set of surroundinginformation based on the acquired time information and the accuracyinformation. Actually, the contribution degree lowest value calculationunit 902 uses the above formula to correct the acquired accuracyinformation based on the acquired time information to calculate thecontribution degree that is the corrected accuracy information.

For example, the contribution degree lowest value calculation unit 902calculates the “elapsed time from when surrounding information wasacquired” using the difference between the time stored in the item “timeinformation” of the dynamic map information 601 and the present time.Then, the contribution degree lowest value calculation unit 902calculates the contribution degree of each set of surroundinginformation using the above formula based on the accuracy informationstored in the item “accuracy information” of the dynamic map information601 and the calculated elapsed time.

Also, the contribution degree lowest value calculation unit 902functions as a calculation unit that calculates the lowest contributiondegree (the contribution degree lowest value) from among the calculatedcontribution degrees of the respective sets of surrounding information.Also, the contribution degree lowest value calculation unit 902transmits the calculated contribution degree lowest value to the vehiclemanagement server 110.

The update unit 903 receives the update instruction transmitted from thevehicle management server 110 together with the update information.Also, the update unit 903 updates the dynamic map information storageunit 122 based on the received update information. For updating thedynamic map information storage unit 122 based on the received updateinformation, the update unit 903 uses the number of stored setscalculated by the number-of-stored-sets calculation unit 901. If theupdate unit 903 has determined that the number of stored sets is lessthan the predetermined number, the update unit 903 stores the receivedupdate information in the dynamic map information storage unit 122. Ifthe update unit 903 has determined that the number of stored sets isgreater than or equal to the predetermined number, the update unit 903removes the set of surrounding information for which the contributiondegree lowest value calculation unit 902 has calculated the contributiondegree lowest value from the dynamic map information storage unit 122,and stores the received update information. Thus, the update unit 903stores the received update information in a manner of replacing the setof surrounding information for which the contribution degree lowestvalue has been calculated with the received update information.

<9. Flow of Surrounding Information Collection Process in SurroundingInformation Collection System>

Next, a flow of a surrounding information collection process in thesurrounding information collection system 100 will be described. FIGS.10 and 11 are sequence diagrams illustrating a surrounding informationcollection process in the surrounding information collection system.

When the vehicle 130 has entered a state where the ignition key has beenturned on in step S1001, the surrounding information acquisition unit201 acquires the surrounding information detected by the surroundinginformation acquisition sensor (for example, the first surroundinginformation acquisition sensor 221). In step S1002, the surroundinginformation acquisition unit 201 associates the acquired surroundinginformation with the position information, the time information, thetype information, and the accuracy information, and records thesurrounding information in the surrounding information recording unit205.

In step S1003, the surrounding information acquisition unit 201 sendsthe position information, the time information, the type information,and the accuracy information recorded and associated with thesurrounding information to the attribution information transmission unit202.

In step S1004, the attribution information transmission unit 202generates the attribution information that includes the positioninformation, the time information, the type information, and theaccuracy information that have been sent from the surroundinginformation acquisition unit 201, and sends the generated attributioninformation to the DCM 141.

In step S1005, the DCM 141 transmits the attribution information thathas been sent from the attribution information transmission unit 202 tothe vehicle management server 110 via the network 150.

In step S1006, the attribute information reception unit 701 receives theattribution information transmitted from the vehicle 130, and extractsthe position information, the time information, the type information,and the accuracy information from the attribution information. Also, theattribute information reception unit 701 reads the area definitioninformation 400 based on the extracted position information, anddetermines the area corresponding to the position information.

In step S1007, the attribute information reception unit 701 sends thearea information that indicates the area determined in step S1006, andthe type information extracted in step S1006, to thenumber-of-stored-sets determination unit 702.

In step S1008, the number-of-stored-sets determination unit 702generates a request that includes the area information and the typeinformation that have been sent from the attribute information receptionunit 701 to calculate the number of stored sets, and transmits therequest to the information management server 120.

In step S1009, the number-of-stored-sets calculation unit 901 of theinformation management server 120 receives the request to calculate thenumber of stored sets from the vehicle management server 110, andextracts the area information and the type information from the request.The number-of-stored-sets calculation unit 901 then reads the dynamicmap information (for example, the dynamic map information 601)corresponding to the extracted area information and type informationfrom the dynamic map information storage unit 122. Thenumber-of-stored-sets calculation unit 901 then calculates the number ofsets of surrounding information (the number of stored sets) included inthe stored dynamic map information that has been read.

In step S1010, the number-of-stored-sets calculation unit 901 transmitsthe calculated number of stored sets to the vehicle management server110.

In step S1011, the number-of-stored-sets determination unit 702 receivesthe number of stored sets transmitted from the information managementserver 120, and determines whether the received number of stored sets isgreater than or equal to the predetermined number. If thenumber-of-stored-sets determination unit 702 determines that thereceived number of stored sets is less than the predetermined number instep S1011 (NO in step S1011), the number-of-stored-sets determinationunit 702 proceeds to step S1012, and sends the determination result tothe transmission requesting unit 705.

On the other hand, if the number-of-stored-sets determination unit 702determines that the received number of stored sets is greater than orequal to the predetermined number in step S1011 (YES in step S1011), thenumber-of-stored-sets determination unit 702 proceeds to step S1013, andsends the determination result to the attribute information receptionunit 701.

The transmission requesting unit 705 that has received the determinationresult from the number-of-stored-sets determination unit 702 transmits arequest to transmit the surrounding information to the vehicle 130 instep S1014.

The DCM 141 that has received the request to transmit the surroundinginformation from the transmission requesting unit 705 sends a request totransmit the surrounding information to the attribution informationtransmission unit 202, in step S1015.

On the other hand, the attribute information reception unit 701 that hasreceived the determination result from the number-of-stored-setsdetermination unit 702 sends the area information, the type information,and the accuracy information to the contribution calculation unit 703 instep S1016.

In step S1017, the contribution calculation unit 703 calculates thecontribution degree using the accuracy information received from theattribute information reception unit 701. In step S1018, thecontribution calculation unit 703 generates a request that includes thearea information and the type information received from the attributeinformation reception unit 701 to calculate the contribution degreelowest value, and transmits the request to the information managementserver 120.

In step S1019, the contribution degree lowest value calculation unit 902receives the request to calculate the contribution degree lowest valuefrom the contribution calculation unit 703, and extracts the areainformation and the type information included in the request. Thecontribution degree lowest value calculation unit 902 then reads thesets of dynamic map information corresponding to the extracted areainformation and type information from the dynamic map informationstorage unit 122. The contribution degree lowest value calculation unit902 then calculates the respective contribution degrees of the sets ofsurrounding information included in the sets of dynamic map informationthat have been read. The contribution degree lowest value calculationunit 902 then calculates the lowest contribution degree (thecontribution degree lowest value) based on the calculated contributiondegrees of the respective sets of surrounding information.

In step S1020, the contribution degree lowest value calculation unit 902transmits the contribution degree lowest value calculated in step S1019to the vehicle management server 110.

In step S1021, the contribution calculation unit 703 receives thecontribution degree lowest value transmitted from the contributiondegree lowest value calculation unit 902, and sends the receivedcontribution degree lowest value, and the contribution degree calculatedin step S1017, to the comparison unit 704.

In step S1022, the comparison unit 704 compares the contribution degreewith the contribution degree lowest value both sent from thecontribution calculation unit 703.

If the comparison unit 704 has determined that the contribution degreeis greater than the contribution degree lowest value, the comparisonunit 704 proceeds to step S1023, and sends the determination result tothe transmission requesting unit 705. If the comparison unit 704 hasdetermined that the contribution degree is less than or equal to thecontribution degree lowest value, the comparison unit 704 does not sendthe determination result to the transmission requesting unit 705.

In step S1024, the transmission requesting unit 705 transmits a requestto transmit the surrounding information to the vehicle 130.

The DCM 141 that has received the request to transmit the surroundinginformation from the transmission requesting unit 705 sends a request totransmit the surrounding information to the attribution informationtransmission unit 202 in step S1025.

Then, in step S1101 of FIG. 11, the attribution information transmissionunit 202 determines whether the attribution information transmissionunit 202 has received a request to transmit the surrounding informationfrom the vehicle management server 110 within a predetermined period oftime from when the attribution information transmission unit 202transmitted the attribution information.

In step S1101, if the attribution information transmission unit 202determines that the attribution information transmission unit 202 hasreceived a request to transmit the surrounding information within thepredetermined period of time, the process proceeds to step S1102. Instep S1102, the surrounding information transmission unit 203 reads thesurrounding information recorded in the surrounding informationrecording unit 205 in step S1002 (FIG. 10) together with the vehicle ID.

In step S1103, the surrounding information transmission unit 203 sendsthe read surrounding information and vehicle ID to the DCM 141. In stepS1104, the DCM 141 transmits the surrounding information and the vehicleID to the vehicle management server 110.

In step S1105, when the surrounding information reception unit 706 hasreceived the surrounding information and the vehicle ID from the vehicle130, the surrounding information reception unit 706 sends a receptionnotification to the attribute information reception unit 701.

In step S1106, in response to the reception notification, the attributeinformation reception unit 701 sends the attribution information (thetime information, the position information, the type information, andthe accuracy information), and the area information to the surroundinginformation reception unit 706. In step S1107, the surroundinginformation reception unit 706 creates update information that includesthe time information, the area information, the position information,the type information, the accuracy information, the surroundinginformation, and the vehicle ID, and sends the update information to theupdate instruction unit 707.

In step S1108, the update instruction unit 707 transmits the updateinformation and an update instruction to the information managementserver 120.

In step S1109, the update unit 903 of the information management server120 stores the update information in the dynamic map information storageunit 122. At this time, the update unit 903 determines whether thenumber of stored sets of surrounding information stored in the dynamicmap information is greater than or equal to the predetermined number. Ifthe update unit 903 determines that the number of stored sets ofsurrounding information is greater than or equal to the predeterminednumber, the update unit 903 deletes the surrounding information that hasthe contribution degree lowest value.

In step S1110, the update unit 903 transmits an update completion reportto the vehicle management server 110.

In step S1114, if the attribute information reception unit 701 hasreceived the update completion report from the information managementserver 120, the attribute information reception unit 701 discards theattribution information and the area information.

On the other hand, if the attribution information transmission unit 202determines that the attribution information transmission unit 202 hasnot received a request to transmit the surrounding information withinthe predetermined period of time in step S1101, the attributioninformation transmission unit 202 discards the surrounding informationthat has been recorded in step S1001 in the surrounding informationrecording unit 205, in step S1111.

In step S1112, the attribution information transmission unit 202 sends arequest invalid response to the DCM 141. In step S1113, the DCM 141transmits the request invalid response to the vehicle management server110.

In step S1114, if the attribute information reception unit 701 hasreceived the request invalid response from the vehicle 130, theattribute information reception unit 701 discards the attributioninformation and the area information.

<10. Actual Example of Surrounding Information Collection Process inSurrounding Information Collection System>

Next, an actual example of the surrounding information collectionprocess in the surrounding information collection system 100 will bedescribed with reference to FIGS. 12-14.

FIG. 12 illustrates a state where a vehicle travels through respectiveplaces where the area definition information has prescribed thecorresponding areas. As illustrated in FIG. 12, it is assumed that avehicle 130 travels on a road indicated by the area definitioninformation 400 along arrows 1201 and 1202.

At this time, the vehicle 130 records the surrounding information in thesurrounding information recording unit 205, and transmits theattribution information to the vehicle management server 110.

The vehicle management server 110 determines that the vehicle 130 haspassed through an area A, an area B, an area C, an area D, and an area Ebased on position information included in the attribution informationtransmitted from the vehicle 130.

FIG. 13 illustrates the surrounding information recording result 510that is recorded in the surrounding information recording unit 205 whilethe vehicle 130 passes through the area A, the area B, the area C, thearea D, and the area E. The zones in FIG. 13 where hatching is providedindicate that a request to transmit the surrounding information has notbeen received from the vehicle management server 110 within thepredetermined period of time from when the attribution information wastransmitted.

On the other hand, white zones in FIG. 13 indicate that a request totransmit the surrounding information has been received from the vehiclemanagement server 110 within the predetermined period of time from whenthe attribution information was transmitted, and that the surroundinginformation has been transmitted to the vehicle management server 110.

Thus, the vehicle 130 transmits only the sets of surrounding information(the white zones) which the vehicle management server 110 has requestedthe vehicle 130 to transmit, from among the sets of surroundinginformation (the hatched zones and the white zones) acquired during thetravel, to the vehicle management server 110. Therefore, in comparisonto a case of transmitting all the sets of surrounding information (thehatched zones and the white zones) acquired during the travel, it ispossible to reduce the number of sets of surrounding information totransmit to the vehicle management server 110. Here, the communicationstraffic required to transmit the surrounding information is much greaterthan the communications traffic required to transmit the attributioninformation. Therefore, by reducing the number of sets of surroundinginformation to transmit to the vehicle management server 110, it ispossible to reduce the communications traffic between the vehicle 130and the vehicle management server 110.

Note that, sets of surrounding information that have not beentransmitted to the vehicle management server 110 are sets of surroundinginformation determined as having low contribution degrees in comparisonto the sets of surrounding information already stored in the dynamic mapinformation storage unit 122 of the information management server 120.Therefore, it can be said that even through sets of surroundinginformation have not been transmitted, likelihood that creation andupdate of the dynamic map is affected is low.

FIG. 14 illustrates a state where each set of dynamic map information inthe dynamic map information storage unit 122 is updated with time.Description will now be made in comparison to FIG. 6. Each set ofdynamic map information illustrated in FIG. 14 is dynamic mapinformation changed from the corresponding one illustrated in FIG. 6 dueto an elapse of a certain period of time. Thus, each set of dynamic mapinformation illustrated in FIG. 14 is partially changed from thecorresponding one illustrated in FIG. 6.

For example, in the example of FIG. 6, the dynamic map information 601has a set of surrounding information (data name “3D target information4-011”) acquired by the vehicle of “vehicle ID=C4” and having “accuracyinformation=2”.

On the other hand, in the example of FIG. 14, the set of surroundinginformation (data name “3D target information 4-011”) is replaced with aset of surrounding information (data name “3D target information16-002”) having “accuracy information=7”.

Note that, also in FIG. 14, the data name (for example, “3D targetinformation 1-001”) of each set of surrounding information is mentionedin the item “surrounding information” for the sake of simplifying theexplanation. Actually, in the item “surrounding information”, thecorresponding set of surrounding information itself is stored.

Thus, according to the surrounding information collection system 100, aset of surrounding information stored in the dynamic map informationstorage unit 122 is replaced with a set of surrounding informationhaving a higher contribution degree with time.

<11. Flow of Surrounding Information Analysis Process in SurroundingInformation Collection System>

Next, a flow of a surrounding information analysis process in thesurrounding information collection system 100 will be described. FIG. 15is a flowchart illustrating a flow of a surrounding information analysisprocess in the surrounding information collection system. In step S1501,the surrounding information analysis unit 708 monitors the updateinstruction unit 707 to determine whether the dynamic map informationstorage unit 122 has been updated.

In step S1501, if the surrounding information analysis unit 708 hasdetermined that the dynamic map information storage unit 122 has notbeen updated, the surrounding information analysis unit 708 ends thesurrounding information analysis process. On the other hand, if thesurrounding information analysis unit 708 has determined that thedynamic map information storage unit 122 has been updated, thesurrounding information analysis unit 708 proceeds to step S1502.

In step S1502, the surrounding information analysis unit 708 determineswhether the fact that the update instruction unit 707 has transmittedthe update information is caused by a request to send the surroundinginformation based on a notification from the number-of-stored-setsdetermination unit 702 or a notification from the comparison unit 704.

If the surrounding information analysis unit 708 has determined that thefact that the update instruction unit 707 has transmitted the updateinformation is caused by a request to send the surrounding informationbased on a notification from the number-of-stored-sets determinationunit 702, the surrounding information analysis unit 708 determines thatthe number of stored sets is less than the predetermined number (NO instep S1502), and ends the surrounding information analysis process.

On the other hand, if the surrounding information analysis unit 708 hasdetermined that the fact that the update instruction unit 707 hastransmitted the update information is caused by a request to send thesurrounding information based on a notification from the comparison unit704, the surrounding information analysis unit 708 determines that thenumber of stored sets is greater than or equal to the predeterminednumber (YES in step S1502), and the surrounding information analysisunit 708 proceeds to step S1503.

In step S1503, the surrounding information analysis unit 708 determinesthe vehicle ID included in the update information transmitted from theupdate instruction unit 707. In step S1504, the surrounding informationanalysis unit 708 determines the user corresponding to the determinedvehicle ID, and increases the score of the determined user.

Thus, according to the surrounding information collection system 100, auser who transmits surrounding information that has a highercontribution degree can acquire a higher score. That is, the user whohas, for example, a classy car that has surrounding informationacquisition sensors capable of detecting surrounding information of highaccuracy can acquire a higher score. As a result, according to thesurrounding information collection system 100, it is possible to give anincentive to a user who maintains a classy car, for example.

Note that there can be various uses of the score that a user acquires.For example, it is possible to reflect the score in an insurance settingfor the user.

<12. Summary of Embodiment>

As can be seen from the above description, the surrounding informationcollection system 100 of the present embodiment has the followingfeatures:

-   -   An information management server corrects accuracy information        associated with stored surrounding information, according to        freshness of the information (i.e., the elapsed time from when        the surrounding information was acquired), to calculate a        contribution degree. Also, the information management server        calculates the lowest contribution degree (the contribution        degree lowest value) from the calculated contribution degrees.    -   If a vehicle has acquired surrounding information, the vehicle        management server receives the accuracy information concerning        the surrounding information from the vehicle. Also, at a timing        when the management server has received the accuracy        information, the vehicle management server acquires the        contribution degree lowest value from the information management        server.    -   Such a control is made that, if the contribution degree        calculated based on the accuracy information received by the        vehicle management server from the vehicle is greater than the        acquired contribution degree lowest value, the information        management server requests the vehicle to transmit the        surrounding information, whereas if the contribution degree        calculated based on the accuracy information is less than or        equal to the acquired contribution degree lowest value, the        information management server does not request the vehicle to        transmit the surrounding information.

Thus, according to the surrounding information collection system 100 ofthe present embodiment, targets to be collected as surroundinginformation are limited, and therefore, it is possible to reducecommunications traffic required for collecting the surroundinginformation.

Thus, according to one aspect of the present disclosure, a surroundinginformation collection system requests a vehicle to transmit surroundinginformation, and stores the surrounding information transmitted from thevehicle in response to the requesting. Therefore, it is possible tocollect surrounding information that is transmitted according to arequest.

Also, according to the aspect, the surrounding information collectionsystem requests a vehicle to transmit surrounding information, thevehicle acquiring the surrounding information greater than a thresholdcalculated based on accuracy of the stored surrounding information.Therefore, it is possible to limit vehicles requested to transmitsurrounding information to vehicles that acquire surrounding informationhaving accuracy greater than the threshold calculated based on theaccuracy of the stored surrounding information. It is also possible tolimit surrounding information to be requested from vehicles intosurrounding information having accuracy greater than the threshold. As aresult, when surrounding information acquired by vehicles is collectedvia a communications network, collection targets are limited. Therefore,it is possible to reduce the communications traffic required to collectthe surrounding information.

Thus, according to the aspect, when surrounding information acquired byvehicles is collected via a communications network, collection targetsare limited based on accuracy of the surrounding information. Therefore,it is possible to reduce the communications traffic required to collectthe surrounding information.

The surrounding information collection systems and the surroundinginformation acquisition apparatuses have been described in theembodiments. However, the present invention is not limited to theseembodiments. Various modifications and improvements can be made withinthe scope of the present invention such as those shown below, forexample.

[Variant No. 1]

In the above-mentioned embodiment, the attribution informationtransmission unit 202 transmits the attribution information thatincludes the position information, the time information, the typeinformation, and the accuracy information to the vehicle managementserver 110, if the surrounding information acquisition unit 201 hasacquired surrounding information. However, the attribution informationtransmission unit 202 may transmit the attribution information withoutregard to whether the surrounding information acquisition unit 201 hasacquired the surrounding information.

Also, in the above-mentioned embodiment, the attribution informationtransmission unit 202 transmits the position information, the timeinformation, the type information, and the accuracy information as theattribution information. However, if the vehicle management server 110associates the type information and the accuracy information with thevehicle ID when the vehicle management server 110 stores the typeinformation and the accuracy information, the attribution informationtransmission unit 202 may transmit the attribution information thatincludes the vehicle ID instead of the type information and the accuracyinformation.

In this case, the vehicle management server 110 does not request thevehicle which has transmitted the accuracy information greater than thecontribution degree lowest value but requests the vehicle (that thevehicle management server 110 previously knows) which can acquire theaccuracy information greater than the contribution degree lowest valueto transmit surrounding information. That is, in the vehicle managementserver 110, the comparison unit 704 need not carry out thedetermination.

[Variant No. 2]

In the above-mentioned embodiment, targets from which surroundinginformation are requested and targets to be requested are limited toreduce the communications traffic required to collect surroundinginformation. However, the surrounding information acquisition apparatus142 (that is, the vehicle 130) itself may determine whether to transmitsurrounding information.

In the accuracy information setting table 500, the sensor types, theaccuracy information, and the type information are prescribed concerningall the surrounding information acquisition sensors that the vehicle 130has. Therefore, the surrounding information transmission unit 203 maytransmit only surrounding information acquired by the surroundinginformation acquisition sensors for which the accuracy informationgreater than a predetermined threshold is prescribed. In this case, thesurrounding information transmission unit 203 functions as adetermination unit that determines whether surrounding informationacquired by a surrounding information acquisition sensor has accuracyhigher than a predetermined threshold. The surrounding informationtransmission unit 203 also functions as a transmission unit thattransmits surrounding information to the vehicle management server 110if the surrounding information transmission unit 203 has determined thatthe surrounding information acquired by a surrounding informationacquisition sensor has accuracy higher than the predetermined threshold.Note that the “predetermined threshold” may be previously set in thesurrounding information acquisition apparatus 142, or may be set inresponse to an instruction sent from the vehicle management server 110.

[Variant No. 3]

In the above-mentioned embodiment, the comparison unit 704 determineswhether to send the determination result to the transmission requestingunit 705 using the contribution degree lowest value calculated based onthe time information and the accuracy information of the surroundinginformation stored in the dynamic map information storage unit 122 as athreshold. However, the threshold to determine whether to send thedetermination result to the transmission requesting unit 705 is notlimited to the contribution degree lowest value. The threshold todetermine whether to send the determination result to the transmissionrequesting unit 705 may be any value calculated based on the timeinformation and the accuracy information of the surrounding informationstored in the dynamic map information storage unit 122 and suitable tocollect the surrounding information that will contribute to creation andupdate of the dynamic map information storage unit 112.

In the above-mentioned embodiment, the dynamic map information storageunit 122 is included in the information management server 120, and theinformation management server 120 functions as the informationmanagement unit 121. However, the dynamic map information storage unit122 need not be included in the information management server 120 thatis a storage unit different from the vehicle management server 110. Forexample, the dynamic map information storage unit 122 may be included ina storage unit in the vehicle management server 110. In this case, thevehicle management server 110 functions as the contributiondetermination unit 111 and the information management unit 121.

Also, in the above-mentioned embodiment, the time information thatindicates the time when the surrounding information detected by asurrounding information acquisition sensor is recorded in thesurrounding information recording unit 205 is stored in the dynamic mapinformation storage unit 122. However, the time information stored inthe dynamic map information storage unit 122 is not limited to theabove-mentioned time information. For example, if the attributioninformation transmission unit 202 transmits the attribution informationto the vehicle management server 110 immediately after the detectedsurrounding information is recorded in the surrounding informationrecording unit 205, the time information that indicates the time whenthe vehicle management server 110 receives the attribution informationmay be stored in the dynamic map information storage unit 122.

Also, in the above-mentioned embodiment, “0” is substituted for the“elapsed time from when surrounding information was acquired” when thecontribution calculation unit 703 of the vehicle management server 110calculates the contribution degree. However, there may be a case where,after a certain time has elapsed since the surrounding informationacquisition unit 201 acquired the surrounding information, theattribution information transmission unit 202 transmits the attributioninformation. Therefore, the contribution calculation unit 703 of thevehicle management server 110 may calculate the contribution degree inthe same calculation method as the method in which the contributiondegree lowest value calculation unit 902 of the information managementserver 120 calculates the contribution degree. That is, also when thecontribution calculation unit 703 of the vehicle management server 110calculates the contribution degree, the difference between the time whenthe calculation is carried out and the time information included in theattribution information may be used to substitute for the “elapsed timefrom when surrounding information was acquired”.

Also, in the above-mentioned embodiment, the contribution calculationunit 703 calculates the contribution degree if the contributioncalculation unit 703 has determined that the number-of-stored-setsdetermination unit 702 of the vehicle management server 110 is greaterthan or equal to the predetermined number. However, the contributioncalculation unit 703 may calculate the contribution degree withoutregard to whether the contribution calculation unit 703 has determinedthat the number-of-stored-sets determination unit 702 of the vehiclemanagement server 110 is greater than or equal to the predeterminednumber. This is because, even if the number of stored sets is small, itis possible to further reduce the communications traffic by excludingsurrounding information that has a low contribution degree from thetargets to be collected.

The present application is based on and claims the benefit of priorityof Japanese Priority Application No. 2016-086243, filed on Apr. 22,2016, the entire contents of which are hereby incorporated herein byreference.

What is claimed is:
 1. A surrounding information collection systemcomprising: one or more processors configured to request a vehicle totransmit surrounding information; and store the surrounding informationtransmitted from the vehicle in response to the requesting, wherein theone or more processors are further configured to request a vehicle totransmit surrounding information, the vehicle acquiring the surroundinginformation having accuracy greater than a threshold calculated based onaccuracy of the stored surrounding information.
 2. The surroundinginformation collection system according to claim 1, wherein the one ormore processors are further configured to receive accuracy ofsurrounding information that a vehicle acquires; determine whether thereceived accuracy is greater than the threshold; and request a vehicleto transmit surrounding information, the vehicle acquiring thesurrounding information for which accuracy is determined to be greaterthan the threshold.
 3. The surrounding information collection systemaccording to claim 1, wherein the one or more processors are furtherconfigured to calculate the threshold using serviceability acquired fromreducing, according to an elapsed time from when surrounding informationhas been acquired by the vehicle, serviceability of the surroundinginformation determined depending on the accuracy of the storedsurrounding information.
 4. The surrounding information collectionsystem according to claim 2, wherein the one or more processors arefurther configured to calculate the threshold using serviceabilityacquired from reducing serviceability of surrounding informationdetermined depending on the accuracy of the stored surroundinginformation according to an elapsed time from when the surroundinginformation has been acquired by the vehicle.
 5. The surroundinginformation collection system according to claim 1, wherein the one ormore processors are further configured to request a vehicle thatacquires surrounding information to transmit the surrounding informationif the number of stored sets of surrounding information is less than apredetermined number.
 6. The surrounding information collection systemaccording to claim 2, wherein the one or more processors are furtherconfigured to request a vehicle that acquires surrounding information totransmit the surrounding information if the number of stored sets ofsurrounding information is less than a predetermined number.
 7. Thesurrounding information collection system according to claim 3, whereinthe one or more processors are further configured to request a vehiclethat acquires surrounding information to transmit the surroundinginformation if the number of stored sets of surrounding information isless than a predetermined number.
 8. The surrounding informationcollection system according to claim 4, wherein the one or moreprocessors are further configured to request a vehicle that acquiressurrounding information to transmit the surrounding information if thenumber of stored sets of surrounding information is less than apredetermined number.
 9. A surrounding information acquisition apparatuscomprising: one or more processors configured to acquire surroundinginformation of a vehicle that includes the surrounding informationacquisition apparatus; determine whether the acquired surroundinginformation has accuracy greater than a threshold; and transmit sets ofsurrounding information, determined to have accuracy greater than thethreshold, from among acquired sets of surrounding information, to avehicle management server that manages the vehicle, the surroundinginformation acquisition apparatus being communicatably connected withthe vehicle management server.